Cardiac defects and altered ryanodine receptor function in mice lacking FKBP12

FKBP12, a cis-trans prolyl isomerase that binds the immunosuppressants FK506 and rapamycin, is ubiquitously expressed and interacts with proteins in several intracellular signal transduction systems(1). Although FKBP12 interacts with the cytoplasmic domains of type I receptors of the transforming growth factor-beta (TGF-beta) superfamily in vitro, the function of FKBP12 in TGF-beta superfamily signalling is controversial(2-6). FKBP12 also physically interacts stoichiometrically with multiple intracellular calcium release channels including the tetrameric skeletal muscle ryanodine dine receptor (RyR1)(7,8). In contrast, the cardiac ryanodine receptor, RyR2, appears to bind selectively the FKBP12 homologue, FKBP12.6 (refs 9, 10). To define the functions of FKBP12 in vivo, we generated mutant mice deficient in FKBP12 using embryonic stem (ES) cell technology. FKBP12-deficient mice have normal skeletal muscle but have severe dilated cardiomyopathy and ventricular septal defects that mimic a human congenital heart disorder, noncompaction of left ventricular myocardium(11,12). About 9% of the mutants exhibit exencephaly secondary to a defect in neural tube closure. Physiological studies demonstrate that FKBP12 is dispensable for TGF-beta-mediated signalling, but modulates the calcium release activity of both skeletal and cardiac ryanodine receptors.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62697/1/391489a0.pd

Social-Ecological Determinants of Elite Student Athletes’ Dual Career Development in Hong Kong and Taiwan

[[abstract]]Previous research has encouraged a cultural specific framework to be developed through research in Asian countries, such as China, to help internationalize the findings and help athletes to adapt them to their society and culture. Based on a socioecological framework, this study investigated how social-ecological determinants affect elite student athletes’ (ESA) experience of the socialization process of dual career development in Hong Kong and Taiwan. We interviewed eight ESAs who trained at the national level, studying simultaneously at universities in Hong Kong and Taiwan. Grounded theory techniques and procedures were used to analyze the data. Results revealed that ESAs are affected by interrelated determinants at different levels: individual (career aims, identities, roles, characters, self-efficacy, and motivation), micro-level (coaches, teammates, parents, siblings, physical education [PE] teachers, other teachers, alumni, seniors, and classmates), meso-level (interrelations between individual and micro-level), exo-level (government, financial, policy, academic, medical, and parent–teacher association), macro-level (attitudes, norms, values, beliefs, resources, and culture), and chrono-level (transition).[[notice]]補正完

Perfectionistic concerns cognitions predict burnout in college athletes: a three-month longitudinal study

The majority of research examining the relationship between perfectionism and athlete burnout has focused on trait perfectionism, while overlooking the importance of the cognitive elements of perfectionism. Perfectionistic cognitions represent an influential cognitive bias driving perfectionistic behavior. Although perfectionistic cognitions have been shown to correlate with burnout symptoms in athletes, this body of work is very limited and does not include college athletes. In addition, it is currently unclear whether perfectionistic cognitions also predict changes in athlete burnout over time. To address these issues, we conducted a two-wave, three month longitudinal study and measured perfectionistic cognitions and burnout in a sample of 170 college athletes both at the start and end of a competitive season. In doing so, we also sought to empirically test the different models of perfectionistic cognitions that have been proposed (original, short, and multidimensional). Using cross-lagged panel models, we found that perfectionistic concerns cognitions predicted increases in burnout. The findings provide initial evidence that perfectionistic cognitions predict changes in athlete burnout over time in college athletes. Consequently, the findings have important implications for our understanding of both athlete burnout and perfectionistic cognitions